Transcript Automatic External Defibrillation

Automatic External
Defibrillation
Aaron J. Katz, AEMT-P, CIC
www.es26medic.net
AHA Chain of Survival
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Early access
Early CPR
Early defibrillation
Early ALS
Cardiac electrophysiology
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SA Node
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“dominant pacemaker”
“Fires” 60-100 times per minute
Internodal pathways
AV Node
Bundle of HIS
Left and right bundle branches
Purkinje network
Nonperfusing heart rhythms
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Ventricular tachycardia (“VTACH”)
Ventricular fibrillation (“VFIB”)
Asystole
Electromechanical dissociation (EMD)
Pulseless electrical activity (PEA)
VTACH
VFIB
Asystole
The bottom line
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All the above abnormal heart rhythms
can not produce a perfusing pulse
Pulseless VTACH and VFIB CAN be
successfully converted to a
perfusing rhythm using a
defibrillator
AED – the technology
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Very accurate computer enabling
recognition of lethal rhythms
(“Analyze”)
Modern AED will talk
Shocking mechanism (“Shock”)
Automatic vs. semiautomatic
Common AED errors
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Bad battery
Patient moving
AED applied to a responsive patient
Bad battery
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Use fully charged batteries
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Depends on manufacturer
Pay attention to AED warnings
about batteries
Bad batteries are uncommon today
COLD WEATHER
Patient moving
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Causes inaccurate analysis
Don’t touch the patient
Stop the bus when analyzing!
AED applied to a responsive patient
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AED applied to a responsive patient
with a rapid pulse
AED may falsely interpret as
VTACH – and recommend shock
Therefore: only apply AED to an
unresponsive pulseless patient
Complications & solutions
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Patient has a pacemaker
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AICD
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Apply pads 5” from pacemaker
No danger to EMT!
Small amount of energy
Apply pads 5” from pacemaker
Very hairy chest
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Shave the area
Keep a disposable razor with your
defibrillator
Integrating AED into CPR
AED integration
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Arrive at the scene
Assess responsiveness
Stop CPR (EMTs or bystanders)
Verify pulselessness & apnea
Resume CPR until AED is ready
*** NOTE WELL ***
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If you are the only rescuer, DO
NOT DO CPR UNTIL THE PATIENT
IS DEFIBRILLATED
The most important life saving
action for the cardiac arrest
patient is defibrillation
Therefore, PREPARE THE
DEFIBRILLATOR!
AED integration – cont’d
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Prepare for defibrillation:
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Bare the chest
Power on AED
Remove nitro paste/patches
Apply pads to the chest
Look at the pads, they show you how
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Right: right of sternum under clavicle
Left: left ribs
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Top of pad should 2-3” below armpit
Apply them smoothly
STOP CPR
AED integration – cont’d
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Make sure no one is touching the
patient
Either press analyze or “Analyze” may
start on its own
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AED may tell you “analyzing – do not touch
the patient”
Results…
AED integration – cont’d
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Analysis at any time will result in either:
Shock advised
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AED will charge and tell you to clear the patient
and press shock
First shock within 90 seconds of AED availability
No shock advised
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Patient may have a pulse
Patient has a nonshockable rhythm
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Asystole, EMD/PEA
Shocks recommended
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Initial analyze/shock up to 3 times
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Check pulse…
Pulse absent?
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CPR for one minute
check pulse, no pulse?
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Three “stacked analyze/shocks”
Three stacked analyze/shocks
We’re now up to 6 shocks
Check pulse
Decision time
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Short transport time?
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Transport
Continue CPR
Long transport time/ALS close?
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3 stacked analyze/shocks
1 minute CPR
Check pulse
Repeat sequence until hospital or until No
Shock Advised
No shock advised
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CPR
Transport
Pulse Present?
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Assess Vital Signs
Support ABCs
Immediate Transport
AED and Children
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Do not use the AED in pediatric cardiac
arrest unless:
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AED is equipped for and FDA approved for
use on children less than 8 years of age
Hypothermic patients & AED
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Limit shocks to 3
After 3 shocks, if needed, CPR,
rewarming and transport